Commit 0c176fa8 authored by Mark A. Greer's avatar Mark A. Greer Committed by Paul Mackerras
Browse files

[POWERPC] Add non-OF serial console support



Add serial console support for non-OF systems.  There is a generic serial
console layer which calls a serial console driver.  Included is the serial
console driver for the ns16550 class of uarts.  Necessary support routines
are added as well.
Signed-off-by: default avatarMark A. Greer <mgreer@mvista.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 6fb4efc6
......@@ -40,8 +40,8 @@ zliblinuxheader := zlib.h zconf.h zutil.h
$(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) \
$(addprefix $(obj)/,$(zlibheader))
src-wlib := string.S stdio.c main.c flatdevtree.c flatdevtree_misc.c div64.S \
$(zlib)
src-wlib := string.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
ns16550.c serial.c div64.S util.S $(zlib)
src-plat := of.c
src-boot := crt0.S $(src-wlib) $(src-plat) empty.c
......
#ifndef _IO_H
#define __IO_H
/*
* Low-level I/O routines.
*
* Copied from <file:include/asm-powerpc/io.h> (which has no copyright)
*/
static inline int in_8(const volatile unsigned char *addr)
{
int ret;
__asm__ __volatile__("lbz%U1%X1 %0,%1; twi 0,%0,0; isync"
: "=r" (ret) : "m" (*addr));
return ret;
}
static inline void out_8(volatile unsigned char *addr, int val)
{
__asm__ __volatile__("stb%U0%X0 %1,%0; sync"
: "=m" (*addr) : "r" (val));
}
static inline unsigned in_le32(const volatile unsigned *addr)
{
unsigned ret;
__asm__ __volatile__("lwbrx %0,0,%1; twi 0,%0,0; isync"
: "=r" (ret) : "r" (addr), "m" (*addr));
return ret;
}
static inline unsigned in_be32(const volatile unsigned *addr)
{
unsigned ret;
__asm__ __volatile__("lwz%U1%X1 %0,%1; twi 0,%0,0; isync"
: "=r" (ret) : "m" (*addr));
return ret;
}
static inline void out_le32(volatile unsigned *addr, int val)
{
__asm__ __volatile__("stwbrx %1,0,%2; sync" : "=m" (*addr)
: "r" (val), "r" (addr));
}
static inline void out_be32(volatile unsigned *addr, int val)
{
__asm__ __volatile__("stw%U0%X0 %1,%0; sync"
: "=m" (*addr) : "r" (val));
}
#endif /* _IO_H */
/*
* 16550 serial console support.
*
* Original copied from <file:arch/ppc/boot/common/ns16550.c>
* (which had no copyright)
* Modifications: 2006 (c) MontaVista Software, Inc.
*
* Modified by: Mark A. Greer <mgreer@mvista.com>
*/
#include <stdarg.h>
#include <stddef.h>
#include "types.h"
#include "string.h"
#include "stdio.h"
#include "io.h"
#include "ops.h"
#define UART_DLL 0 /* Out: Divisor Latch Low */
#define UART_DLM 1 /* Out: Divisor Latch High */
#define UART_FCR 2 /* Out: FIFO Control Register */
#define UART_LCR 3 /* Out: Line Control Register */
#define UART_MCR 4 /* Out: Modem Control Register */
#define UART_LSR 5 /* In: Line Status Register */
#define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */
#define UART_LSR_DR 0x01 /* Receiver data ready */
#define UART_MSR 6 /* In: Modem Status Register */
#define UART_SCR 7 /* I/O: Scratch Register */
static unsigned char *reg_base;
static u32 reg_shift;
static int ns16550_open(void)
{
out_8(reg_base + (UART_FCR << reg_shift), 0x06);
return 0;
}
static void ns16550_putc(unsigned char c)
{
while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0);
out_8(reg_base, c);
}
static unsigned char ns16550_getc(void)
{
while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0);
return in_8(reg_base);
}
static u8 ns16550_tstc(void)
{
return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0);
}
int ns16550_console_init(void *devp, struct serial_console_data *scdp)
{
int n;
n = getprop(devp, "virtual-reg", &reg_base, sizeof(reg_base));
if (n != sizeof(reg_base))
return -1;
n = getprop(devp, "reg-shift", &reg_shift, sizeof(reg_shift));
if (n != sizeof(reg_shift))
reg_shift = 0;
scdp->open = ns16550_open;
scdp->putc = ns16550_putc;
scdp->getc = ns16550_getc;
scdp->tstc = ns16550_tstc;
scdp->close = NULL;
return 0;
}
/*
* Generic serial console support
*
* Author: Mark A. Greer <mgreer@mvista.com>
*
* Code in serial_edit_cmdline() copied from <file:arch/ppc/boot/simple/misc.c>
* and was written by Matt Porter <mporter@kernel.crashing.org>.
*
* 2001,2006 (c) MontaVista Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <stdarg.h>
#include <stddef.h>
#include "types.h"
#include "string.h"
#include "stdio.h"
#include "io.h"
#include "ops.h"
extern void udelay(long delay);
static int serial_open(void)
{
struct serial_console_data *scdp = console_ops.data;
return scdp->open();
}
static void serial_write(char *buf, int len)
{
struct serial_console_data *scdp = console_ops.data;
while (*buf != '\0')
scdp->putc(*buf++);
}
static void serial_edit_cmdline(char *buf, int len)
{
int timer = 0, count;
char ch, *cp;
struct serial_console_data *scdp = console_ops.data;
cp = buf;
count = strlen(buf);
cp = &buf[count];
count++;
while (timer++ < 5*1000) {
if (scdp->tstc()) {
while (((ch = scdp->getc()) != '\n') && (ch != '\r')) {
/* Test for backspace/delete */
if ((ch == '\b') || (ch == '\177')) {
if (cp != buf) {
cp--;
count--;
printf("\b \b");
}
/* Test for ^x/^u (and wipe the line) */
} else if ((ch == '\030') || (ch == '\025')) {
while (cp != buf) {
cp--;
count--;
printf("\b \b");
}
} else if (count < len) {
*cp++ = ch;
count++;
scdp->putc(ch);
}
}
break; /* Exit 'timer' loop */
}
udelay(1000); /* 1 msec */
}
*cp = 0;
}
static void serial_close(void)
{
struct serial_console_data *scdp = console_ops.data;
if (scdp->close)
scdp->close();
}
static void *serial_get_stdout_devp(void)
{
void *devp;
char devtype[MAX_PROP_LEN];
char path[MAX_PATH_LEN];
devp = finddevice("/chosen");
if (devp == NULL)
goto err_out;
if (getprop(devp, "linux,stdout-path", path, MAX_PATH_LEN) > 0) {
devp = finddevice(path);
if (devp == NULL)
goto err_out;
if ((getprop(devp, "device_type", devtype, sizeof(devtype)) > 0)
&& !strcmp(devtype, "serial"))
return devp;
}
err_out:
return NULL;
}
static struct serial_console_data serial_cd;
/* Node's "compatible" property determines which serial driver to use */
int serial_console_init(void)
{
void *devp;
int rc = -1;
char compat[MAX_PROP_LEN];
devp = serial_get_stdout_devp();
if (devp == NULL)
goto err_out;
if (getprop(devp, "compatible", compat, sizeof(compat)) < 0)
goto err_out;
if (!strcmp(compat, "ns16550"))
rc = ns16550_console_init(devp, &serial_cd);
/* Add other serial console driver calls here */
if (!rc) {
console_ops.open = serial_open;
console_ops.write = serial_write;
console_ops.edit_cmdline = serial_edit_cmdline;
console_ops.close = serial_close;
console_ops.data = &serial_cd;
return 0;
}
err_out:
return -1;
}
/*
* Copied from <file:arch/powerpc/kernel/misc_32.S>
*
* This file contains miscellaneous low-level functions.
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
* and Paul Mackerras.
*
* kexec bits:
* Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
* GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include "ppc_asm.h"
#define SPRN_PVR 0x11F /* Processor Version Register */
.text
/* udelay (on non-601 processors) needs to know the period of the
* timebase in nanoseconds. This used to be hardcoded to be 60ns
* (period of 66MHz/4). Now a variable is used that is initialized to
* 60 for backward compatibility, but it can be overridden as necessary
* with code something like this:
* extern unsigned long timebase_period_ns;
* timebase_period_ns = 1000000000 / bd->bi_tbfreq;
*/
.data
.globl timebase_period_ns
timebase_period_ns:
.long 60
.text
/*
* Delay for a number of microseconds
*/
.globl udelay
udelay:
mfspr r4,SPRN_PVR
srwi r4,r4,16
cmpwi 0,r4,1 /* 601 ? */
bne .udelay_not_601
00: li r0,86 /* Instructions / microsecond? */
mtctr r0
10: addi r0,r0,0 /* NOP */
bdnz 10b
subic. r3,r3,1
bne 00b
blr
.udelay_not_601:
mulli r4,r3,1000 /* nanoseconds */
/* Change r4 to be the number of ticks using:
* (nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns
* timebase_period_ns defaults to 60 (16.6MHz) */
mflr r5
bl 0f
0: mflr r6
mtlr r5
lis r5,0b@ha
addi r5,r5,0b@l
subf r5,r5,r6 /* In case we're relocated */
addis r5,r5,timebase_period_ns@ha
lwz r5,timebase_period_ns@l(r5)
add r4,r4,r5
addi r4,r4,-1
divw r4,r4,r5 /* BUS ticks */
1: mftbu r5
mftb r6
mftbu r7
cmpw 0,r5,r7
bne 1b /* Get [synced] base time */
addc r9,r6,r4 /* Compute end time */
addze r8,r5
2: mftbu r5
cmpw 0,r5,r8
blt 2b
bgt 3f
mftb r6
cmpw 0,r6,r9
blt 2b
3: blr
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment